Computing and networking technology have transformed our world. As the amount of information communicated over networks has increased, high speed transmission has become ever more critical. Many high speed data transmission networks rely on optical transceivers and similar devices for facilitating transmission and reception of digital data embodied in the form of optical signals over optical fibers. Optical networks are thus found in a wide variety of high speed applications ranging from as modest as a small Local Area Network (LAN) to as grandiose as the backbone of the Internet.
In many applications, optical transceivers are implemented as a module of various form factors such as SFP and the like. The module typically includes the various electronic and optical components necessary for data transmission such as the laser diode, laser driver, photo-diode, and post-amplifier enclosed in a shell or encasing, typically made of metal. It is often desirable for the module to be hot-pluggable, which permits the module to be inserted and removed from a module card cage or other similar device without removing electrical power.
One common difficulty associated with the operation such modules is the generation of electromagnetic radiation. The generation of electromagnetic radiation by a module is a matter of significant concern because such electromagnetic radiation can cause electromagnetic interference (EMI) with other systems and devices in the vicinity, which can seriously impair, if not prevent, the proper operation of those other systems and devices.
In addition, when the modules are plugged into a module card cage or like, they generate heat that must be accounted for. If the heat is not properly dissipated or transferred away from the module, damage may occur to the module. Thus, the control of EMI effects and heat transfer are important considerations in the design and use of hot-pluggable modules.